How to handle concurrent QT versions

[Alexander Asteroth]

Dear all,

since two month I didn't update my guix system now since I have a few
self compiled softwares that depend on QT@5.15 (qtbase, etc.) which I
need every day. Now version 6 of QT replaces 5 everywhere and whithout
updating to 6 I cannot update a lot of other packages.

How do you guys handle this situation? Or am I the only one facing this
problem.

Cheers,
Alex